Electrode material for vapor electric apparatus.



UNITED STATES PATEN T OFFICE.

RAY I. JACKSON, 0F EDGEWOOD PARK, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

ELECTRODE MATERIAL FOR VAPOR ELECTRIC APPARATUS.

No Drawing.

To all whom it may concern:

Be it known that I, RAY P. JACKSON, a citizen of the United States, and a resident of Edgewood Park, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Electrode Materials for Vapor Electric Apparatus, of which the following is a specification.

My invention relates to vapor-electric apparatus such as mercury-vapor lamps and current rectifiers, and particularly to the composition of the vaporizable electrode material.

The object of my invention is to provide a material for the vaporizable electrode of vapor-electric apparatus having such a composition that it will not plate or permanently coat the inner surface of the casing of the vacuum chamber.

In vapor-electric apparatus, it has here-- tofore been customary to employ pure mercury as the material for the vaporizable electrode, which, however, after varying periods of use, frequently plates or permancntly coats substantially the whole inner surface of the casing of the vacuum chamher. The inner surface of the casing, therefore, becomes conducting, and, as a result, the rectifying operation is more or less unsteady and sub ect to frequent stoppages. The quantity of mercury originally in the pool or pools constituting the cathode also becomes materially reduced, thereby requiring the employment of a greater quantity of mercury than would otherwise be necessary Specification of Letters Patent.

Application filed July 17, 1912. Serial No. 710,077.

Patented June 9, 1914.

for the purpose of maintaining a pool of sufficient depth for efficient and satisfactory operation.

I have found that the addition of a small amount of pure lead to the mercury serves to greatly reduce and substantially prevent the plating or coating of the inner surface of the casing, thereby rendering the apparatus much less subject to stoppage and avoiding all other troubles which have heretofore been caused by the plating. While variable amounts of lead may be employed, I have found that from one to two hundredths of one per cent. of lead is sufficient to accomplish the desired result, and I prefer to employ approximately two hundredths of one per cent. of lead in the cathode.

I claim as my invention:

1. A vaporizable electrode for vapor electric apparatus composed of mercury and a fractional percentage of lead.

2. A vaporizable electrode for vapor electric apparatus composed of mercury and a small amount of lead that does not exc ed two hundredths of one per cent.

3. A vaporizable electrode for vapor electric apparatus composed exclusively of mercury and a very small percentage of lead.

In testimony whereof, I have hereunto subscribed my name this 5th day of July, 1912.

R. P. J AOKSON.

Witnesses:

CLAYTON DILL. B. B. Hmns. 

